Merge tag 'tty-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial / console fixes from Greg KH:
 "Here are a bunch of fixes/reverts for 6.10-rc6.  Include in here are:

   - revert the bunch of tty/serial/console changes that landed in -rc1
     that didn't quite work properly yet.

     Everyone agreed to just revert them for now and will work on making
     them better for a future release instead of trying to quick fix the
     existing changes this late in the release cycle

   - 8250 driver port count bugfix

   - Other tiny serial port bugfixes for reported issues

  All of these have been in linux-next this week with no reported
  issues"

* tag 'tty-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "printk: Save console options for add_preferred_console_match()"
  Revert "printk: Don't try to parse DEVNAME:0.0 console options"
  Revert "printk: Flag register_console() if console is set on command line"
  Revert "serial: core: Add support for DEVNAME:0.0 style naming for kernel console"
  Revert "serial: core: Handle serial console options"
  Revert "serial: 8250: Add preferred console in serial8250_isa_init_ports()"
  Revert "Documentation: kernel-parameters: Add DEVNAME:0.0 format for serial ports"
  Revert "serial: 8250: Fix add preferred console for serial8250_isa_init_ports()"
  Revert "serial: core: Fix ifdef for serial base console functions"
  serial: bcm63xx-uart: fix tx after conversion to uart_port_tx_limited()
  serial: core: introduce uart_port_tx_limited_flags()
  Revert "serial: core: only stop transmit when HW fifo is empty"
  serial: imx: set receiver level before starting uart
  tty: mcf: MCF54418 has 10 UARTS
  serial: 8250_omap: Implementation of Errata i2310
  tty: serial: 8250: Fix port count mismatch with the device

Documentation/admin-guide/kernel-parameters.txt

@@ -788,25 +788,6 @@
 			Documentation/networking/netconsole.rst for an
 			alternative.
 
-		<DEVNAME>:<n>.<n>[,options]
-			Use the specified serial port on the serial core bus.
-			The addressing uses DEVNAME of the physical serial port
-			device, followed by the serial core controller instance,
-			and the serial port instance. The options are the same
-			as documented for the ttyS addressing above.
-
-			The mapping of the serial ports to the tty instances
-			can be viewed with:
-
-			$ ls -d /sys/bus/serial-base/devices/*:*.*/tty/*
-			/sys/bus/serial-base/devices/00:04:0.0/tty/ttyS0
-
-			In the above example, the console can be addressed with
-			console=00:04:0.0. Note that a console addressed this
-			way will only get added when the related device driver
-			is ready. The use of an earlycon parameter in addition to
-			the console may be desired for console output early on.
-
 		uart[8250],io,<addr>[,options]
 		uart[8250],mmio,<addr>[,options]
 		uart[8250],mmio16,<addr>[,options]

drivers/tty/serial/8250/8250_core.c

@@ -15,7 +15,6 @@
  */
 
 #include <linux/acpi.h>
-#include <linux/cleanup.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/ioport.h>
@@ -42,8 +41,6 @@
 
 #include <asm/irq.h>
 
-#include "../serial_base.h"	/* For serial_base_add_isa_preferred_console() */
-
 #include "8250.h"
 
 /*
@@ -563,8 +560,6 @@ static void __init serial8250_isa_init_ports(void)
 		port->irqflags |= irqflag;
 		if (serial8250_isa_config != NULL)
 			serial8250_isa_config(i, &up->port, &up->capabilities);
-
-		serial_base_add_isa_preferred_console(serial8250_reg.dev_name, i);
 	}
 }
 

drivers/tty/serial/8250/8250_omap.c

@@ -115,6 +115,10 @@
 /* RX FIFO occupancy indicator */
 #define UART_OMAP_RX_LVL		0x19
 
+/* Timeout low and High */
+#define UART_OMAP_TO_L                 0x26
+#define UART_OMAP_TO_H                 0x27
+
 /*
  * Copy of the genpd flags for the console.
  * Only used if console suspend is disabled
@@ -663,13 +667,24 @@ static irqreturn_t omap8250_irq(int irq, void *dev_id)
 
 	/*
 	 * On K3 SoCs, it is observed that RX TIMEOUT is signalled after
-	 * FIFO has been drained, in which case a dummy read of RX FIFO
-	 * is required to clear RX TIMEOUT condition.
+	 * FIFO has been drained or erroneously.
+	 * So apply solution of Errata i2310 as mentioned in
+	 * https://www.ti.com/lit/pdf/sprz536
 	 */
 	if (priv->habit & UART_RX_TIMEOUT_QUIRK &&
-	    (iir & UART_IIR_RX_TIMEOUT) == UART_IIR_RX_TIMEOUT &&
-	    serial_port_in(port, UART_OMAP_RX_LVL) == 0) {
-		serial_port_in(port, UART_RX);
+		(iir & UART_IIR_RX_TIMEOUT) == UART_IIR_RX_TIMEOUT) {
+		unsigned char efr2, timeout_h, timeout_l;
+
+		efr2 = serial_in(up, UART_OMAP_EFR2);
+		timeout_h = serial_in(up, UART_OMAP_TO_H);
+		timeout_l = serial_in(up, UART_OMAP_TO_L);
+		serial_out(up, UART_OMAP_TO_H, 0xFF);
+		serial_out(up, UART_OMAP_TO_L, 0xFF);
+		serial_out(up, UART_OMAP_EFR2, UART_OMAP_EFR2_TIMEOUT_BEHAVE);
+		serial_in(up, UART_IIR);
+		serial_out(up, UART_OMAP_EFR2, efr2);
+		serial_out(up, UART_OMAP_TO_H, timeout_h);
+		serial_out(up, UART_OMAP_TO_L, timeout_l);
 	}
 
 	/* Stop processing interrupts on input overrun */

drivers/tty/serial/8250/8250_pci.c

@@ -1985,6 +1985,17 @@ enum {
 	MOXA_SUPP_RS485 = BIT(2),
 };
 
+static unsigned short moxa_get_nports(unsigned short device)
+{
+	switch (device) {
+	case PCI_DEVICE_ID_MOXA_CP116E_A_A:
+	case PCI_DEVICE_ID_MOXA_CP116E_A_B:
+		return 8;
+	}
+
+	return FIELD_GET(0x00F0, device);
+}
+
 static bool pci_moxa_is_mini_pcie(unsigned short device)
 {
 	if (device == PCI_DEVICE_ID_MOXA_CP102N	||
@@ -2038,7 +2049,7 @@ static int pci_moxa_init(struct pci_dev *dev)
 {
 	unsigned short device = dev->device;
 	resource_size_t iobar_addr = pci_resource_start(dev, 2);
-	unsigned int num_ports = (device & 0x00F0) >> 4, i;
+	unsigned int i, num_ports = moxa_get_nports(device);
 	u8 val, init_mode = MOXA_RS232;
 
 	if (!(pci_moxa_supported_rs(dev) & MOXA_SUPP_RS232)) {

drivers/tty/serial/bcm63xx_uart.c

@@ -308,8 +308,8 @@ static void bcm_uart_do_tx(struct uart_port *port)
 
 	val = bcm_uart_readl(port, UART_MCTL_REG);
 	val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
-
-	pending = uart_port_tx_limited(port, ch, port->fifosize - val,
+	pending = uart_port_tx_limited_flags(port, ch, UART_TX_NOSTOP,
+		port->fifosize - val,
 		true,
 		bcm_uart_writel(port, ch, UART_FIFO_REG),
 		({}));
@@ -320,6 +320,9 @@ static void bcm_uart_do_tx(struct uart_port *port)
 	val = bcm_uart_readl(port, UART_IR_REG);
 	val &= ~UART_TX_INT_MASK;
 	bcm_uart_writel(port, val, UART_IR_REG);
+
+	if (uart_tx_stopped(port))
+		bcm_uart_stop_tx(port);
 }
 
 /*

drivers/tty/serial/imx.c

@@ -1952,8 +1952,10 @@ static int imx_uart_rs485_config(struct uart_port *port, struct ktermios *termio
 
 	/* Make sure Rx is enabled in case Tx is active with Rx disabled */
 	if (!(rs485conf->flags & SER_RS485_ENABLED) ||
-	    rs485conf->flags & SER_RS485_RX_DURING_TX)
+	    rs485conf->flags & SER_RS485_RX_DURING_TX) {
+		imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);
 		imx_uart_start_rx(port);
+	}
 
 	return 0;
 }

drivers/tty/serial/mcf.c

@@ -462,7 +462,7 @@ static const struct uart_ops mcf_uart_ops = {
 	.verify_port	= mcf_verify_port,
 };
 
-static struct mcf_uart mcf_ports[4];
+static struct mcf_uart mcf_ports[10];
 
 #define	MCF_MAXPORTS	ARRAY_SIZE(mcf_ports)
 

drivers/tty/serial/serial_base.h

@@ -49,33 +49,3 @@ void serial_ctrl_unregister_port(struct uart_driver *drv, struct uart_port *port
 
 int serial_core_register_port(struct uart_driver *drv, struct uart_port *port);
 void serial_core_unregister_port(struct uart_driver *drv, struct uart_port *port);
-
-#ifdef CONFIG_SERIAL_CORE_CONSOLE
-
-int serial_base_add_preferred_console(struct uart_driver *drv,
-				      struct uart_port *port);
-
-#else
-
-static inline
-int serial_base_add_preferred_console(struct uart_driver *drv,
-				      struct uart_port *port)
-{
-	return 0;
-}
-
-#endif
-
-#ifdef CONFIG_SERIAL_8250_CONSOLE
-
-int serial_base_add_isa_preferred_console(const char *name, int idx);
-
-#else
-
-static inline
-int serial_base_add_isa_preferred_console(const char *name, int idx)
-{
-	return 0;
-}
-
-#endif

drivers/tty/serial/serial_base_bus.c

@@ -8,7 +8,6 @@
  * The serial core bus manages the serial core controller instances.
  */
 
-#include <linux/cleanup.h>
 #include <linux/container_of.h>
 #include <linux/device.h>
 #include <linux/idr.h>
@@ -205,134 +204,6 @@ void serial_base_port_device_remove(struct serial_port_device *port_dev)
 	put_device(&port_dev->dev);
 }
 
-#ifdef CONFIG_SERIAL_CORE_CONSOLE
-
-static int serial_base_add_one_prefcon(const char *match, const char *dev_name,
-				       int port_id)
-{
-	int ret;
-
-	ret = add_preferred_console_match(match, dev_name, port_id);
-	if (ret == -ENOENT)
-		return 0;
-
-	return ret;
-}
-
-#ifdef __sparc__
-
-/* Handle Sparc ttya and ttyb options as done in console_setup() */
-static int serial_base_add_sparc_console(const char *dev_name, int idx)
-{
-	const char *name;
-
-	switch (idx) {
-	case 0:
-		name = "ttya";
-		break;
-	case 1:
-		name = "ttyb";
-		break;
-	default:
-		return 0;
-	}
-
-	return serial_base_add_one_prefcon(name, dev_name, idx);
-}
-
-#else
-
-static inline int serial_base_add_sparc_console(const char *dev_name, int idx)
-{
-	return 0;
-}
-
-#endif
-
-static int serial_base_add_prefcon(const char *name, int idx)
-{
-	const char *char_match __free(kfree) = NULL;
-	const char *nmbr_match __free(kfree) = NULL;
-	int ret;
-
-	/* Handle ttyS specific options */
-	if (strstarts(name, "ttyS")) {
-		/* No name, just a number */
-		nmbr_match = kasprintf(GFP_KERNEL, "%i", idx);
-		if (!nmbr_match)
-			return -ENODEV;
-
-		ret = serial_base_add_one_prefcon(nmbr_match, name, idx);
-		if (ret)
-			return ret;
-
-		/* Sparc ttya and ttyb */
-		ret = serial_base_add_sparc_console(name, idx);
-		if (ret)
-			return ret;
-	}
-
-	/* Handle the traditional character device name style console=ttyS0 */
-	char_match = kasprintf(GFP_KERNEL, "%s%i", name, idx);
-	if (!char_match)
-		return -ENOMEM;
-
-	return serial_base_add_one_prefcon(char_match, name, idx);
-}
-
-/**
- * serial_base_add_preferred_console - Adds a preferred console
- * @drv: Serial port device driver
- * @port: Serial port instance
- *
- * Tries to add a preferred console for a serial port if specified in the
- * kernel command line. Supports both the traditional character device such
- * as console=ttyS0, and a hardware addressing based console=DEVNAME:0.0
- * style name.
- *
- * Translates the kernel command line option using a hardware based addressing
- * console=DEVNAME:0.0 to the serial port character device such as ttyS0.
- * Cannot be called early for ISA ports, depends on struct device.
- *
- * Note that duplicates are ignored by add_preferred_console().
- *
- * Return: 0 on success, negative error code on failure.
- */
-int serial_base_add_preferred_console(struct uart_driver *drv,
-				      struct uart_port *port)
-{
-	const char *port_match __free(kfree) = NULL;
-	int ret;
-
-	ret = serial_base_add_prefcon(drv->dev_name, port->line);
-	if (ret)
-		return ret;
-
-	port_match = kasprintf(GFP_KERNEL, "%s:%i.%i", dev_name(port->dev),
-			       port->ctrl_id, port->port_id);
-	if (!port_match)
-		return -ENOMEM;
-
-	/* Translate a hardware addressing style console=DEVNAME:0.0 */
-	return serial_base_add_one_prefcon(port_match, drv->dev_name, port->line);
-}
-
-#endif
-
-#ifdef CONFIG_SERIAL_8250_CONSOLE
-
-/*
- * Early ISA ports initialize the console before there is no struct device.
- * This should be only called from serial8250_isa_init_preferred_console(),
- * other callers are likely wrong and should rely on earlycon instead.
- */
-int serial_base_add_isa_preferred_console(const char *name, int idx)
-{
-	return serial_base_add_prefcon(name, idx);
-}
-
-#endif
-
 static int serial_base_init(void)
 {
 	int ret;

drivers/tty/serial/serial_core.c

@@ -3422,10 +3422,6 @@ int serial_core_register_port(struct uart_driver *drv, struct uart_port *port)
 	if (ret)
 		goto err_unregister_ctrl_dev;
 
-	ret = serial_base_add_preferred_console(drv, port);
-	if (ret)
-		goto err_unregister_port_dev;
-
 	ret = serial_core_add_one_port(drv, port);
 	if (ret)
 		goto err_unregister_port_dev;

include/linux/printk.h

@@ -60,9 +60,6 @@ static inline const char *printk_skip_headers(const char *buffer)
 #define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT
 #define CONSOLE_LOGLEVEL_QUIET	 CONFIG_CONSOLE_LOGLEVEL_QUIET
 
-int add_preferred_console_match(const char *match, const char *name,
-				const short idx);
-
 extern int console_printk[];
 
 #define console_loglevel (console_printk[0])

include/linux/serial_core.h

@@ -811,8 +811,7 @@ enum UART_TX_FLAGS {
 	if (pending < WAKEUP_CHARS) {					      \
 		uart_write_wakeup(__port);				      \
 									      \
-		if (!((flags) & UART_TX_NOSTOP) && pending == 0 &&	      \
-		    __port->ops->tx_empty(__port))			      \
+		if (!((flags) & UART_TX_NOSTOP) && pending == 0)	      \
 			__port->ops->stop_tx(__port);			      \
 	}								      \
 									      \
@@ -851,6 +850,24 @@ enum UART_TX_FLAGS {
 			__count--);					      \
 })
 
+/**
+ * uart_port_tx_limited_flags -- transmit helper for uart_port with count limiting with flags
+ * @port: uart port
+ * @ch: variable to store a character to be written to the HW
+ * @flags: %UART_TX_NOSTOP or similar
+ * @count: a limit of characters to send
+ * @tx_ready: can HW accept more data function
+ * @put_char: function to write a character
+ * @tx_done: function to call after the loop is done
+ *
+ * See uart_port_tx_limited() for more details.
+ */
+#define uart_port_tx_limited_flags(port, ch, flags, count, tx_ready, put_char, tx_done) ({ \
+	unsigned int __count = (count);							   \
+	__uart_port_tx(port, ch, flags, tx_ready, put_char, tx_done, __count,		   \
+			__count--);							   \
+})
+
 /**
  * uart_port_tx -- transmit helper for uart_port
  * @port: uart port

kernel/printk/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-obj-y	= printk.o conopt.o
+obj-y	= printk.o
 obj-$(CONFIG_PRINTK)	+= printk_safe.o nbcon.o
 obj-$(CONFIG_A11Y_BRAILLE_CONSOLE)	+= braille.o
 obj-$(CONFIG_PRINTK_INDEX)	+= index.o

kernel/printk/conopt.c

-// SPDX-License-Identifier: GPL-2.0
-/*
- * Kernel command line console options for hardware based addressing
- *
- * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
- * Author: Tony Lindgren <tony@atomide.com>
- */
-
-#include <linux/console.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/types.h>
-
-#include <asm/errno.h>
-
-#include "console_cmdline.h"
-
-/*
- * Allow longer DEVNAME:0.0 style console naming such as abcd0000.serial:0.0
- * in addition to the legacy ttyS0 style naming.
- */
-#define CONSOLE_NAME_MAX	32
-
-#define CONSOLE_OPT_MAX		16
-#define CONSOLE_BRL_OPT_MAX	16
-
-struct console_option {
-	char name[CONSOLE_NAME_MAX];
-	char opt[CONSOLE_OPT_MAX];
-	char brl_opt[CONSOLE_BRL_OPT_MAX];
-	u8 has_brl_opt:1;
-};
-
-/* Updated only at console_setup() time, no locking needed */
-static struct console_option conopt[MAX_CMDLINECONSOLES];
-
-/**
- * console_opt_save - Saves kernel command line console option for driver use
- * @str: Kernel command line console name and option
- * @brl_opt: Braille console options
- *
- * Saves a kernel command line console option for driver subsystems to use for
- * adding a preferred console during init. Called from console_setup() only.
- *
- * Return: 0 on success, negative error code on failure.
- */
-int __init console_opt_save(const char *str, const char *brl_opt)
-{
-	struct console_option *con;
-	size_t namelen, optlen;
-	const char *opt;
-	int i;
-
-	namelen = strcspn(str, ",");
-	if (namelen == 0 || namelen >= CONSOLE_NAME_MAX)
-		return -EINVAL;
-
-	opt = str + namelen;
-	if (*opt == ',')
-		opt++;
-
-	optlen = strlen(opt);
-	if (optlen >= CONSOLE_OPT_MAX)
-		return -EINVAL;
-
-	for (i = 0; i < MAX_CMDLINECONSOLES; i++) {
-		con = &conopt[i];
-
-		if (con->name[0]) {
-			if (!strncmp(str, con->name, namelen))
-				return 0;
-			continue;
-		}
-
-		/*
-		 * The name isn't terminated, only opt is. Empty opt is fine,
-		 * but brl_opt can be either empty or NULL. For more info, see
-		 * _braille_console_setup().
-		 */
-		strscpy(con->name, str, namelen + 1);
-		strscpy(con->opt, opt, CONSOLE_OPT_MAX);
-		if (brl_opt) {
-			strscpy(con->brl_opt, brl_opt, CONSOLE_BRL_OPT_MAX);
-			con->has_brl_opt = 1;
-		}
-
-		return 0;
-	}
-
-	return -ENOMEM;
-}
-
-static struct console_option *console_opt_find(const char *name)
-{
-	struct console_option *con;
-	int i;
-
-	for (i = 0; i < MAX_CMDLINECONSOLES; i++) {
-		con = &conopt[i];
-		if (!strcmp(name, con->name))
-			return con;
-	}
-
-	return NULL;
-}
-
-/**
- * add_preferred_console_match - Adds a preferred console if a match is found
- * @match: Expected console on kernel command line, such as console=DEVNAME:0.0
- * @name: Name of the console character device to add such as ttyS
- * @idx: Index for the console
- *
- * Allows driver subsystems to add a console after translating the command
- * line name to the character device name used for the console. Options are
- * added automatically based on the kernel command line. Duplicate preferred
- * consoles are ignored by __add_preferred_console().
- *
- * Return: 0 on success, negative error code on failure.
- */
-int add_preferred_console_match(const char *match, const char *name,
-				const short idx)
-{
-	struct console_option *con;
-	char *brl_opt = NULL;
-
-	if (!match || !strlen(match) || !name || !strlen(name) ||
-	    idx < 0)
-		return -EINVAL;
-
-	con = console_opt_find(match);
-	if (!con)
-		return -ENOENT;
-
-	/*
-	 * See __add_preferred_console(). It checks for NULL brl_options to set
-	 * the preferred_console flag. Empty brl_opt instead of NULL leads into
-	 * the preferred_console flag not set, and CON_CONSDEV not being set,
-	 * and the boot console won't get disabled at the end of console_setup().
-	 */
-	if (con->has_brl_opt)
-		brl_opt = con->brl_opt;
-
-	console_opt_add_preferred_console(name, idx, con->opt, brl_opt);
-
-	return 0;
-}

kernel/printk/console_cmdline.h

@@ -2,12 +2,6 @@
 #ifndef _CONSOLE_CMDLINE_H
 #define _CONSOLE_CMDLINE_H
 
-#define MAX_CMDLINECONSOLES 8
-
-int console_opt_save(const char *str, const char *brl_opt);
-int console_opt_add_preferred_console(const char *name, const short idx,
-				      char *options, char *brl_options);
-
 struct console_cmdline
 {
 	char	name[16];			/* Name of the driver	    */

kernel/printk/printk.c

@@ -383,6 +383,9 @@ static int console_locked;
 /*
  *	Array of consoles built from command line options (console=)
  */
+
+#define MAX_CMDLINECONSOLES 8
+
 static struct console_cmdline console_cmdline[MAX_CMDLINECONSOLES];
 
 static int preferred_console = -1;
@@ -2500,17 +2503,6 @@ static int __init console_setup(char *str)
 	if (_braille_console_setup(&str, &brl_options))
 		return 1;
 
-	/* Save the console for driver subsystem use */
-	if (console_opt_save(str, brl_options))
-		return 1;
-
-	/* Flag register_console() to not call try_enable_default_console() */
-	console_set_on_cmdline = 1;
-
-	/* Don't attempt to parse a DEVNAME:0.0 style console */
-	if (strchr(str, ':'))
-		return 1;
-
 	/*
 	 * Decode str into name, index, options.
 	 */
@@ -2541,13 +2533,6 @@ static int __init console_setup(char *str)
 }
 __setup("console=", console_setup);
 
-/* Only called from add_preferred_console_match() */
-int console_opt_add_preferred_console(const char *name, const short idx,
-				      char *options, char *brl_options)
-{
-	return __add_preferred_console(name, idx, options, brl_options, true);
-}
-
 /**
  * add_preferred_console - add a device to the list of preferred consoles.
  * @name: device name
@@ -3522,7 +3507,7 @@ void register_console(struct console *newcon)
 	 * Note that a console with tty binding will have CON_CONSDEV
 	 * flag set and will be first in the list.
 	 */
-	if (preferred_console < 0 && !console_set_on_cmdline) {
+	if (preferred_console < 0) {
 		if (hlist_empty(&console_list) || !console_first()->device ||
 		    console_first()->flags & CON_BOOT) {
 			try_enable_default_console(newcon);